The Iron Skull was possibly the first "cyborg" character in comics. He fought a number of robotic minions, including four legged automatons with teeth called "Spider-Mechs." There were tons of robotic minions in comics, used by villains like The Claw.

In the PD movie serial "The Undersea Kingdom" we were introduced to robotic minions called "Volkites" and in the PD Superman serial "The Mechanical Monsters" the titular monsters are 10-15 foot robots with super strength, flight and flamethrowers for eyes. While Superman is not PD, the mechanical monsters are.

Moxon's robot, from the Ambrose Bierce short story "Moxon's Master"Tik-Tok, from the L. Frank Baum "Oz" booksThe eponymous android from The Steam Man of the Prairies (circa 1868)and I think Frank Reade might have built a steam man or clockwork type of robot as well.